A container terminal for holding shipping containers and a method of distributing shipping containers within a stacking yard of a container terminal

Abstract

A method of distributing refrigerated shipping containers 4A within a stacking yard 2 of a container terminal 1 to increase the efficacy of the container terminal. The reefers 4A are arranged in multi

Description

The present invention relates to a container terminal and a method of distributing shipping containers, in particular refrigerated shipping containers within a stacking yard of a container terminal to increase the efficacy of the container terminal. A container terminal (or container port) is a facility for the movement and storage of cargo containers also known as intermodal containers, between different transport vehicles. Container terminals that are adapted to load and unload containers from ships are known as marine container terminals. Those configured only for movement between land vehicles are known as inland container terminals or inland container depots. The present invention is applicable to either but is expected to provide especial benefit to marine container terminals. Figure 1A is a schematic elevation view of a conventional marine container terminal comprising quayside 1, container stacking yard 2 and landside access 3. Imported shipping containers 4 arriving on a ship 5 berthed at the quayside 1 are offloaded using a quay crane 6 and transported from the quayside 1 to a waterside end of the stacking yard 2. Here they are lifted and transported into the stacking yard 2 by a stacking gantry crane 7. When a container 4 is to be retrieved from the yard 2, one of the gantry cranes 7 lifts and transports the container 4 to the landside access 3 where it can be loaded onto a lorry, train or other transport vehicle 8. A similar process but in reverse is used for export shipping containers. Figure IB is a plan view schematic illustrating a conventional configuration of shipping containers within the stacking yard 2. Shipping containers 4 are arranged in blocks 9. Each block 9 has one or more dedicated gantry cranes 7, in this example two, assigned to it. In large terminals blocks are often grouped into modules 18. Each block 9 is comprised from multiple rows 10 of bays 11. For operational and space efficiency reasons, each row 10 is often formed of between eight to ten bays. Typically a block 9 will comprise a greater number of rows 10 than bays 11 per row 10. Each bay 11 is able to hold multiple shipping containers 4 arranged in a vertically stacked configuration. The maximum stacking height depends on the gantry crane 7 used, but is typically six containers 4 high. Shipping containers 4 are commonly one of two classes: refrigerated containers, also known as reefers, which comprise a refrigeration system to control the climate within the interior of the shipping container, typically for carrying perishable goods, and ‘dry’ containers which don’t comprise a refrigeration system. Both dry containers and reefers can be sealed and are weatherproof to protect the goods within them during transport. Reefers are required to be connected to an electrical supply to power the refrigeration equipment and this is conventionally achieved by means of a power cable with plug that plugs into a power socket. The plugging / unplugging is carried out manually by a port operative within the stacking yard. For stacking reefers more than two high, permanent access structures 12, as illustrated in Fig 2, are required to provide port operatives with safe access to the reefers’ power cables. Additionally, protective covered walkways may be required to provide safe access to reefers within a stack. The conventional reefer access gantry structure 12 of Fig 2 provides manual access to a stack of reefers 4A. In this example the structure 12 can accommodate stacks of reefers up to three high, and six wide. The gantry structure 12 comprises a multi-level walkway with steps 13 between each level. The structure 12 carries electrical cables (not shown) that supply electrical power from a power supply 14, typically three-phase, to sockets 15 on each level. An operator climbs the gantry 12 to gain access to the reefers 4A and sockets 15 for the purpose of connecting and disconnecting power cables 16 of the reefers 4 A into the sockets 15. Reefers 4A are typically grouped into a single cluster 17 of rows 10 within a block 9 (see Fig IB) and the plugging and unplugging of reefers within the cluster 17 are scheduled in batches to reduce the number of manual access events required and the time to complete them. To optimise container handling efficiency within the block the cluster 17 is typically located within the middle third of the block 9 between the land and water sides. Such a configuration is shown in the example shown in Fig IB. A disadvantage of locating the cluster centrally within a block 9 is the need to include bypass zones 19 adjacent the rows of reefers 4A to allow transport of containers 4 by gantry crane 7 past the reefers 4A within a block 9. Further, a general problem with providing provisioning for reefers, irrespective of the placement of the cluster 17 within the block 9, is the need to halt or restrict movement of gantry cranes 7 to allow manual access to the reefers 4A for plugging and unplugging. Additionally, the provision of permanent access gantry structures 12 is costly and occupies space that could otherwise be used to hold shipping containers. Because of the disadvantages associated in providing provisioning for reefers 4A, a module 18 is typically laid out so only some of the blocks 9 within a module 18 have reefer provisioning. This increases the operational efficiency of the module 18 as a whole, though can detract from the operational efficiency of loading and unloading reefers from a ship. US9546054 describes a conventional stacking yard layout similar to that described above. CN103887894, DE102017107307, WO2014095016 and JP2011205780 each propose use of wireless inductive charging to supply electrical power to a reefer. According to a first aspect of the invention there is provided a container terminal comprising a stacking yard for holding shipping containers; wherein the shipping containers are arranged in blocks; the container terminal comprising container handling equipment to move shipping containers into and out of the stacking yard; each block comprised of multiple rows of bays, each bay able to hold multiple shipping containers in a vertical stack; and wherein the container terminal comprises an electrical power supply circuitry comprising multiple wireless power transmitter units to supply electrical power to multiple refrigerated containers (reefers) within the stacking yard through wireless power transmission; the multiple wireless power transmitter units arranged as a first set for powering a first group of reefers occupying a first group of one or more contiguous bays within a first block, and a second set for powering a second group of reefers occupying a second group of one or more contiguous bays within the first block; wherein the first and second sets of wireless power transmitter units are arranged such that the first group of one or more bays is non-contiguous to the second group of one or more bays. The provision of wireless power transfer within a stacking yard obviates the need for manual access to reefers within the stacking yard. The invention came about, at least in part, from the realisation that with the constraint to provide manual access removed, operational efficiency can be further improved by decentralised stacking of reefer provisioning throughout a block, and optionally also more homogenously throughout a module. This means that rather than having highly centralised storage blocks for reefers, the storage locations for reefers can be more widely distributed throughout the terminal (subject also to optimising locations of supply substations and cabling etc.) thereby increasing efficiency of the terminal in terms of utilisation of space and the deployment of container handling equipment irrespective of its type, e.g. automatic stacking cranes (ASCs), rail mounted gantry cranes (RMGs), rubber tyred gantry cranes (RTGs), Straddle Carriers, or Reach Stackers. Favourably, there also comprises a third set of wireless power transmitter units arranged to power a third group of reefers occupying a third group of one or more contiguous bays within the block; the third group of one or more contiguous bays being non-contiguous with the first group of one or more contiguous bays and the second group of one or more contiguous bays. The first group of one or more contiguous bays may comprise multiple bays that lie directly adjacent one another within a row and / or bays lying directly opposite one another in directly adjacent row. The second group of one or more contiguous bays may comprise multiple bays that lie directly adjacent one another within a row and / or bays lying directly opposite one another in directly adjacent rows. The third group of one or more contiguous bays may comprise multiple bays that lie directly adjacent one another within a row and / or bays lying directly opposite one another in directly adj acent rows. Each group may be separated by one or more rows of bays that have no access to an electrical power supply and thus are reserved for one or more of dry containers, open frame containers, e.g. tanktainers, and / or non-operating reefers. Nevertheless, it is possible for multiple groupings to include bays from within the same row but which are not directly adjacent one another. The multiple wireless power transmitter units may lie between adjacent rows of the multiple rows. The stacking yard may comprise elongate spaced-apart upright elements; each upright element carrying multiple of the wireless power transmitter units for supplying electrical power wirelessly to a different reefer within a stack of reefers within a bay. The multiple elongate spaced-apart upright elements may be unconnected to one another. Multiple of the elongate upright elements may lie between adjacent rows of the block. Where so the upright elements of the row may be spaced apart from one another by a distance of between 8 feet (2.438m) and 10 feet (3.048m). The elongate spaced-apart upright elements may be arranged into at least two sets; a first set arranged between a first pair of adjacent rows within the block, and a second set between a second pair of adjacent rows within the block; the rows of the first pair being different to the rows of second pair. The container handling equipment may comprise sets of one or more stacking gantry cranes associated with each block to move shipping containers into and out of their respective block. According to another aspect of the invention there is provided a method of distributing shipping containers, comprising dry shipping containers and reefers, within a stacking yard, wherein the shipping containers are arranged in blocks; the method comprising grouping the reefers into multiple non-contiguous groups within a block interspaced by dry shipping containers and / or non-operating reefers; and supplying electrical power to each of the reefers within the multiple non-contiguous groups through wireless power transfer. The invention will now be described by way of the example with reference to the follow figures in which: Figure 1A is a side elevation schematic view of a conventional marine container terminal; Figure IB is a plan view schematic illustrating the layout of containers within the stacking yard of the marine container terminal of Figure 1 A; Figure 2 is a perspective view of a stack of reefers and prior art multi-level gantry structure carrying a power distribution system; Figure 3A is a side elevation schematic view of a marine container terminal comprising a power supply for wirelessly powering reefers; Figure 3B is a plan view schematic illustration of a layout of containers within the stacking yard of the terminal of Figure 3 A; Figure 4 is a schematic of an electrical power supply circuit for wirelessly powering reefers stored within the stacking yard; and Figure 5 is a perspective view of a stack of reefers and a wireless power distribution system comprising a set of spaced apart upright members. Figure 3 A illustrates a marine container terminal comprising a quayside 1, a container stacking yard 2 and a landside access 3. Imported shipping containers 4, including reefers 4A, arriving on a ship 5 berthed at the quayside 1 are offloaded using a quay crane 6 and transported from the quayside 1 to a waterside end of the stacking yard 2. Here they are lifted and transported into the stacking yard 2 by a stacking gantry crane 7. When a container 4 is to be retrieved from the stacking yard 2, one of the gantry cranes 7 lifts and transports the container 4 to the landside access 3 where it can be loaded onto a lorry, train or other transport vehicle 8. A similar process but in reverse is used for export shipping containers. As in the present example, each block 9 may have two dedicated stacking gantry cranes 7 associated with it to increase container handling speed. The gantry cranes 7 may be automated, remotely operated or locally manually operated. They may be end loaded or side loaded (cantilever). In this example the gantry cranes are configured to run on rails 7A but may instead travel on tyred (pneumatic or solid) wheels. Figure 3B is a plan view schematic illustrating an arrangement of shipping containers 4 within the stacking yard 2. The reefers 4A are differentiated from other shipping containers, e.g. the dry containers, non-operating reefers (NORS) and open frame containers by solid shading. NORs are reefers not in active use, e.g. because they are empty or being used to carry non-perishable goods. Shipping containers are arranged in blocks 9, each block 9 having associated with it a dedicated gantry crane 7. The blocks 9 are grouped as a module 18. Each block 9 is comprised from multiple rows 10 of bays 11. In this example each row 10 comprises ten bays, though this is not to be taken as limiting. Each block 9 may comprise many more rows 10 than bays 11 per row 10. Each bay 11 is sized to hold a single vertical stack of containers 4. The container terminal comprises electrical power supply circuitry 100, illustrated schematically in Fig 4, to supply electrical power to reefers 4 A within the stacking yard 2. The power supply circuitry 100 comprises multiple wireless power transmitter units 101, each fed by a central electrical power supply 102 through a power distribution network comprising cabling 103 and optionally power dividers. Although less preferred, the power supply 2 may be located elsewhere within the container terminal 1. With reference also to Fig 3B, the wireless power transmitting units 101 are grouped into multiple sets 110, each set 110 arranged to power a different grouping 120A -120C of reefers 4A within a block 9. Each grouping 120 comprises reefers 4A lying within contiguous bays 11, in this example that being directly adjacent bays within the same row 10, though it could also include bays 11 lying directly opposite one another in directly adjacent rows. Each grouping 120A-120C of reefers 4A within the same block 9 are non-contiguous with the other groupings 120, typically separated by one or more rows of bays 11 that have no access to an electrical power supply and thus are reserved for other types of shipping container, e.g. dry containers, open frame containers and / or NORs. In the present example, the wireless power transmitting units 101 are arranged to provide three groupings 120 of reefers 4A per block 9: a waterside group 120A, a central group 120B and a landside group 120C. Each grouping 120A, 120B, 120C is separated from its neighbouring group by multiple rows comprised exclusively from one or more of dry containers, open frame containers and / or NORs. The arrangement illustrated in Fig 3B provides the same reefer storage capacity as the arrangement of Fig IB of the prior art but distributed more evenly both across each block 9 and the whole module 18. This aids to increase the handling speed and / or handling efficiency of the module 18 as a whole as it enables all waterside stacking gantry cranes 7 of the module 18 to be engaged in handling reefers into and out of the module 18. This arrangement also increases handling speed and / or handling efficacy by reducing the total travel distance along the block 9 for a crane to transport multiple reefers between the waterside and a suitable position within the stacking yard 2, which increases the speed that a ship 5 can be unloaded and loaded. It also provides this benefit at the landside end, though this is usually less commercially important to terminal operators. Fig 5 illustrates an example grouping 120 of reefers within a block 9, a set 110 of wireless power transmitter units to supply electrical power to the grouping, and structure for physically supporting the transmitter units 101 in position. The grouping 120 comprises a single row 10 of bays 9 in which in each is a vertical stack of reefers 4A. In this example, the stack is three reefers high, and row is six bays wide, though this should not be taken as limiting. The grouping 120 may be as wide as the number of bays 11 of the row 10 though this is not essential. Each reefer 4A comprises a refrigeration unit, not shown, to control the temperature within the reefer’s interior, and a wireless power receiver unit 104 configured to receive electrical power wirelessly through induction from one of the wireless power transmitter units 101 to power the refrigeration unit. The reefer 4A may also include power circuitry, which may form part of the wireless power receiver unit 104, configured to one or more of: transform, rectify, invert and convert (e.g. one to three phase) the electrical power received from the wireless power transmitter unit 101 to make it compatible to supply the refrigeration unit. This may be of particular value where the wireless power receiver unit 104 is retrofitted to the reefer 10. The power receiver unit 104 may be integrated into the reefer 104 or may have been retro-fitted following manufacture. The power receiver unit 104 may have been mounted to the reefer 104 following its arrival at the terminal, e.g. manually by port operatives in the quayside 1. To allow mounting to the reefer 4A on arrival at the terminal, the power receiver unit 104 may comprise an electrical output connector adapted to mate with a corresponding external electrical connector of the reefer 4A to supply electrical power to the reefer 4A. Also shown in Figure 5 is a line of vertical upright posts 105, one for each bay 10 in the row 9. Each post 105 is anchored (e.g. set into the ground such as by concreted in) at a spacing of X from its nearest neighbour(s), where X is at least 8ft (2.4m) and favourably at most 10 ft (3.05m). The line of posts is positioned directly between bays of two adjacent rows 10 of the block, see Fig 3B. Each post 105 carries three wireless power transmitter units 101, one for each of the three stacked reefers 4A per bay 11. The wireless power transmitter units 101 are spaced apart vertically from one another to align with the height of the receiving power units 104 of the stacked reefers 4A. A typical vertical spacing between wireless power transmitter units 101 along each post 105 is nine foot six inches (2.9m), corresponding to the height of a Hi-Cube reefer unit, which is now the most common form of reefer. Through this arrangement, the posts 105 carry an array of wireless power transmitter units 101, one for each reefer 4A stacked within the bay; each transmitter unit 101 lying face-to-face with a different receiver unit 104. The preferred maximum spacing between a transmitter unit 101 and a receiver unit 104 of a reefer to which it will be paired for power transmission, is 50cm. This aligns with a preferred working separation around 40cm ± 10cm, which is sufficiently close to enable efficient inductive energy transfer whilst minimising risk of the reefer hitting the transmitted unit when being lifted in and out of the bay. The preferred lateral misalignment in axes transverse to the principal direction of wireless energy transfer to allow for efficient energy transfer between the transmitter unit 101 and receiver unit 104 is no more than 5cm. This should be readily achievable as a misalignment tolerance of <5cm in the relative positioning of shipping containers 4 within a stack is already common working practice to ensure stability of the stack. The electrical leads 103 run up the posts 105. The leads 103 may be carried within the posts 105, or secured externally to them. In operation, electrical power is transmitted wirelessly, through induction, from each of the transmitting units 101 to the receiving units 104 to power the refrigeration units of the reefers 4A. Each wireless power transmitter unit 101 includes a control system including a sensor, e.g. an electro-magnetic sensor, configured to detect the presence of the receiver unit 104 within a proximity of 40cm ± 10cm, and, in response, to regulate the power used by the wireless induction circuitry of the unit 104. This mechanism allows the power consumed by the wireless power transmitter unit 101 to be minimised when there is no reefer 4A to power. This could instead be carried out manually by a dock operator remote from the stacking yard. The receiver unit 104 may include means to transmit power requirement information wirelessly to the wireless power transmitter unit 101, e.g. using a very short-range RF protocol, and the control system configured, in response to receiving said information to regulate the power transmitted. This also serves to improve the overall electrical efficiency of the system, as the power supplied to the reefer can be cycled to match the time-varying power requirement of the refrigeration unit - e.g. as the compressor and / or fans are automatically switched on and off by the reefer’s internal control systems. Ideally, the posts 105 require no lateral supporting structure as this simplifies construction and maintenance. Nevertheless, there may be occasions where the presence of lateral supports between posts 105 are preferred. It will be appreciated that each block 9 may have a different number of groupings 120 5 of reefers 4A per block than three, e.g. two groupings, four or more groupings. Further, different blocks 9 within the same module 18 may have different number of groupings. Although the invention is described in relation to a marine container terminal configured to transfer containers between ships and land vehicles, it will be appreciated that it could equally be used for a trans-shipment marine container terminal, where 10 containers arrive by sea and leave by sea, as well as inland container terminals. It will be appreciated that each post 105 may carry a different number of wireless power transmitters, e.g. (but not limited to) four, five or six, to accord with the maximum stack height of the block.

Claims

1. A container terminal comprising a stacking yard for holding shipping containers; wherein the shipping containers are arranged in blocks; the container terminal comprising container handling equipment to move shipping containers into and out of the stacking yard;each block comprised of multiple rows of bays, each bay able to hold multiple shipping containers in a vertical stack;and wherein the container terminal comprises an electrical power supply circuitry comprising multiple wireless power transmitter units to supply electrical power to multiple refrigerated containers (reefers) within the stacking yard through wireless power transmission;the multiple wireless power transmitter units arranged as a first set for powering a first group of reefers occupying a first group of one or more contiguous bays within a first block, and a second set for powering a second group of reefers occupying a second group of one or more contiguous bays within the first block; wherein the first and second sets of wireless power transmitter units are arranged such that the first group of one or more bays is non-contiguous to the second group of one or more bays.

2. A container terminal according to claim 1 wherein the multiple wireless power transmitter units may lie between adjacent rows of the multiple rows.

3. A container terminal according to claim 1 or 2 comprising elongate spacedapart upright elements; each upright element carrying more than one of the multiple wireless power transmitter units for supplying electrical power wirelessly to each reefer within one of the vertical stacks of reefers within one of the bays.

4. A container terminal according to claim 1, 2 or 3 wherein the container handlingequipment comprises stacking gantry cranes.

5. A method of distributing shipping containers comprising dry and reefer shipping containers within a stacking yard of a container terminal, wherein the shipping containers are arranged in blocks;the method comprising grouping the reefer shipping containers into multiple non-5 contiguous groups within a block interspaced by dry shipping containers and / or nonoperating reefers; and supplying electrical power to each of the reefer shipping containers within the multiple non-contiguous groups through wireless power transfer.14 07 25Claims1. A container terminal comprising a stacking yard for holding shipping containers; wherein the shipping containers are arranged in blocks; the container terminal comprising container handling equipment to move shipping containers into 5 and out of the stacking yard;each block comprised of multiple rows of bays, each bay able to hold multiple shipping containers in a vertical stack;and wherein the container terminal comprises an electrical power supply circuitry comprising multiple wireless power transmitter units to supply electrical power to 10 multiple refrigerated containers (reefers) within the stacking yard through wireless power transmission;the multiple wireless power transmitter units arranged as a first set for powering a first group of reefers occupying a first group of one or more contiguous bays within a first block, and a second set for powering a second group of reefers occupying a second 15 group of one or more contiguous bays within the first block; wherein the first andsecond sets of wireless power transmitter units are arranged such that the first group of one or more bays is non-contiguous to the second group of one or more bays.

2. A container terminal according to claim 1 wherein the multiple wireless power transmitter units lie between adjacent rows of the multiple rows.20 3. A container terminal according to claim 1 or 2 comprising elongate spacedapart upright elements; each upright element carrying more than one of the multiple wireless power transmitter units for supplying electrical power wirelessly to each reefer within one of the vertical stacks of reefers within one of the bays.

4. A container terminal according to claim 1, 2 or 3 wherein the container handling 25 equipment comprises stacking gantry cranes.

5. A method of distributing shipping containers comprising dry and reefer shipping containers within a stacking yard of a container terminal, wherein the shipping containers are arranged in blocks;the method comprising grouping the reefer shipping containers into multiple non-5 contiguous groups within a block interspaced by dry shipping containers and / or nonoperating reefers; and supplying electrical power to each of the reefer shipping containers within the multiple non-contiguous groups through wireless power transfer.

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